Refrigerating system



May 29, 1934- J. H. DENNEDY 1,960,576

REFRIGERATING SYSTEM Filed May l, 1930 2 Sheets-Sheet l d* MVV 1 wm May29, 1934- J. H. DENNEDY 1,960,576

REFRIGERATING SYSTEM Filed Ma,r l. 1930 2 Sheets-Sheet 2 Fine/afmfo/vanaaf 0IA COOL EP Patented May 29, 1934 REFRIGEBATING SYSTEM JamesH. Dennedy, Evansville, Ind., assignor to Botorite Corporation, Detroit,Mich., a corporation of Illinois Application May 1, 1930, Serial No.448,816

12 Claims. (Cl. 62-115) 'Ihis invention relates to a refrigeratingsystem and more particularly to a system in which the motor andcompressor are hermetically sealed Within the system in such a mannerthat loss of refrigerant through a packing about the motor shaft leadingto the compressor is impossible since the motor casing comprises aportion of the refrigerant circulating system.

An object of this invention is the provision of an improved method andmeans whereby the motor may be cooled.

In systems of this type it has heretofore been proposed to pass highpressure refrigerant from the compressor directly through the motorhousing on its way to the condenser and thereby cool the motor, but-thismethod has not been successful on account of the fact that thecompressed refrigerant as it leaves the compressor is relatively hot andwill not absorb sullicient heat from the motor to adequately cool thesame.

Another object of my invention is to provide means for cooling the motorwith refrigerant in a manner to obviate the above objection, and morespecifically to provide a cooling element through which the refrigerantmust pass while moving from the compressor to the motor compartment. l

In general, my invention comprises a compound housing consisting of amotor casing'and a compressor casing, which casings are sealed to apartition which separates them and forms two compartments both of whichare in the refrigerant circulating system. The compressor is adapted toreceive refrigerant from the low pressure side of the system andcompress it, discharging the same into the casing about the compressor,from which it passes through an roil separator and thence to apreliminary cooling element which condenses a portion of therefrigerant, in practice about twenty-five per cent thereof, whichcondensed. refrigerant together with the uncondensed is led into themotor compartment where it extracts heat from the motor, causing it toagain vaporize. The refrigerant gas discharged from the motor casingpasses through the main condenser and from there to the receiver andexpansion coils.

In the accompanying drawings, in which a specific embodiment of myinvention is illustrated,

Figure 1 is a Vertical longitudinal section of the compressor and motorunit constructed in accordance with my invention;

Figure 2 is a vertical cross section taken on y the line 2-2 of Figure1; and

Figure 3 is a diagrammatic illustration of a typical circulating systemincorporating my invention.

Referring to Figures 1 and 2, the compoundI housing 5 for the compressor6 and the motor 7 00 comprises a motor casing 8 and a compressor casing9, which casings are suitably secured in rm engagement with oppositesides of the partition elementv 1l and have suitable gaskets 12 and 13interposed between the partition and the casings for making a hermeticseal therewith so that none of the refrigerant can escape into thesurrounding atmosphere.

The compressor may be of any conventional type comprising a rotatingelement 14 having vanes 15 which draw refrigerant into the compressorthrough the pipe line 16 and port 17, after which it is compressed anddischarged through the passageway 18 and through the passageway 19 andport 21 through the head 22 into the space 23 Within the compressorhousing.

A preliminary cooling coil 24 has communication with the interior of thecompressor compartment 23 through the medium of a vertical passageway 25in the upper edge of the partition 11, and through the conduit 26 andoil separator 27. The coil 2.4 passes around the motor housing asufiicient number of times to provide ample radiating surface throughwhich heat may pass for the purpose of allowing part of the refrigeranttherein to become condensed. The opposite end of the coil 24 hascommunication with a passageway 29 inthe motor casing, which passagewaycommunicates with all parts of the interior of the motor compartment.The condensed refrigerant coming into contact With the motor 7 extractsheat therefrom to cool the motor and becomes again fully vaporized andpasses out of the motor casing and to the main condenser unit 32 throughthe medium of a conduit 33.

A motor 7 is preferably of the squirrel cage induction type asillustrated, having the conducting bars 34 and end rings 35 permanentlyfixed thereto. The stator 37 may have any suitable type of windingthereon for producing the necessary rotating eld and theelectrical'conductors leading to the winding must be suitably sealedwhere they pass through the motor casing.

'I'he fan 42 which cools the condenser 32 is driven by an independentmotor 43 through the motor shaft 44. The condensed refrigerant passesfrom the condenser through the conduit 46 and to the receiving chamber47, from which it is controllably admitted to the expansion coils 48illustrated diagrammatically only in Fig. 3.

5 partially filled with oil 52 which is drawn through the conduits 53and 54, through which it is conducted to the oil cooler 55, which ispreferably a portion of the main condenser as shown in Figure 1. 'Ihecooled oil passes from the cooler 55 through the conduit 56 and back tothe compressor as shown in Figure 2.

'I'he motor shaft 65 is journalled in suitable sleeve lubricatingbearings 66 and 67 for simplifying the lubricating system and insuringlong and continuous operation of the refrigerating unit without thenecessity of repair or replacement. In case oil should be entrained intothe motor compartment along with the refrigerant, suitable means may beprovided such as a conduit 69 for conducting the oil therefrom to thereceiver 47, from which it is carried through the expansion coils andback to the compressor.

It will be understood by those skilled in the art that variousmodifications may be devised for accomplishing the objects of thisinvention and I therefore desire to avail myself of such modications ascome within the scope of the appended claims.

I claim as my invention.

1. In a refrigerating system in combination, a sealed casing including acompressor compartment and a motor compartment, a compressor and a motorin their respective compartments operably connected together, saidcompressor being adapted to receive low pressure gas from outside saidcasing and compress it, discharging it under high pressure into saidcompressor compartment, a preliminary cooler communicating with saidcompressor compartment and adapted to discharge commingled, compressedgaseous and condensed refrigerant into the motor compartment for coolingthe motor, and a condenser communicating with said motor compartment forfully liquefying gas discharged therefrom.

2. In a refrigerating system in combination, a sealed casing including amotor compartment and a compressor compartment, a motor and a compressoroperably connected together and positioned in their respectivecompartments, said compressor being adapted to compress refrigerant anddischarge it into the compressor compartment, cooling meanscommunicating with said compartments for conducting refrigerant from oneto the other while condensing a portion of the same, and a refrigerantcondenser communicating with said motor compartment to condenserefrigerant discharged therefrom.

3. In a refrigerating system in combination, a refrigerant compressor, amotor operably connected with said compressor, cooling means for saidmotor comprising a casing, and a cooling coil for conducting compressedrefrigerant from the compressor to the interior of the motor casing andcondensing a portion thereof, and means for condensing refrigerantdischarged from said motor casing.

4. In a refrigerating system in combination, a refrigerant compressor,and a motor for operating the same, a casing about said compressor forreceiving oil and refrigerant discharged therefrom under high pressure,a sealed motor casing, a cooler communicating with and adapted toconduct refrigerant from the compressor casing to the motor casing andcondense a portion of the same, and means for condensing the refrigerantdischarged from the motor casing.

5. In a device of the class described, a motor. a sealed casing aboutsaid motor, means for partially condensing gaseous refrigerant anddelivering commingled gaseous and condensed refrigerant under pressureto said motor casing for cooling said motor, and means for condensingthe refrigerant discharged from the motor casing.

6. In a hermetically sealed refrlgerating system, a compressor and motorunit hermetically sealed within the system, a casing for the motor, apreliminary cooling element adapted to receive gaseous refrigerant underpressure from said compressor, partially condense the refrigerant anddeliver it to the interior of the motor casing, and means for condensingthe refrigerant discharged from the motor casing.

'1. The method of cooling a motor which is sealed in a refrigeratingsystem including a compressor and refrigerant, which consists of passingcompressed refrigerant gas from the compressor through a cooler forpartially condensing the same, then passing the commingled gaseous andcondensed refrigerant through the motor.

8. In a hermetically sealed refrigerating system comprising a compressorand a motor for operating the same, a casing for said motor, means forcooling and partially condensing the compressed refrigerant anddelivering it in a commingled state to the motor casing, and a condenserfor liquefying the refrigerant discharged from the motor casing.

9. In a refrigerating system comprising a hermetically sealedrefrigerating circuit including a compressor, a casing about thecompressor forming a compartment for containing gaseous refrigerantunder pressure, a motor operably connected with said compressor, acasing for said motor forming a compartment therefor, a partitionbetween the compartments having its edge fixed to said casings, anauxiliary condenser coinmunicating with the compressor compartment forreceiving refrigerant therefrom and partially condensing the same, anddischarging the refrigerant into the motor casing, and a main condenserhaving communication with the discharge of the motor casing.

10. In a refrigerating system comprising a hermetically sealedrefrigerating circuit including a compressor, a casing about thecompressor forming a compartment for containing gaseous refrigerantunder pressure, a motor operably connected with said compressor, anauxiliary condenser communicating with the condenser compartment forreceiving refrigerant therefrom and partially condensing the same, meanscommunicating with said auxiliary condenser adapted to conductrefrigerant therefrom into heat exchange relation with said motor, and amain condenser for receiving and fully liquefying refrigerant dischargedfrom the last said means.

1l. The method of cooling the compressor motor of a refrigeratingapparatus which consists in passing substantially all of the circulatingrefrigerant in series through a circuit, in the course of which circuitthe compressed gaseous refrigerant is first partially condensed, thenpassed into heat exchange relation with the motor to revaporize some ofthe condensed refrigerant and then passing the refrigerant into acondenser, the refrigerant at the region of the first and secondmentioned condensings and at the region of the heat exchange relationbeing at substantially the same pressure.

12. A refrigerating system having a motor for the compressor andcomprising a circuit for a refrigerant consisting, in order, of a lowpressure expansion chamber, said compressor, a rst condenser, a chamberin heat absorbing relation to the motor, a second condenser (the firstcon-

